While Quantitative Methods on Politics (1928) written by S. A. Rice has been rated to be worthy of pilot writings within "four landmarks in voting behavior" (P. H. Rossi) , one may say that the history of researches would extend almost for a century, dating back to the statistical analyses of election results by S. F. Chapin or W. F. Ogburn. And yet, the scientific researches, properly so called, have grown up almost from sociological researches, such as the Erie Study on the 1940 American Presidential election, and have been further promoted by psychological ones, such as the Michigan teams conducted first the survey on a nationwide scale. Added to these, the mathematical analyses of voting behavior centering around rational-choice model have recently attracted the researchers' concern. None the less, it is not too much to say that the status quo of researches is no better than the technical refinement of research methods and the interpretation of findings. A purpose of this paper is to pursue the possibility toward theoretical competition and synthesis around the voting behavior with examining the substances of established theories critically. For all that, it s indispensable for us to review the major theories with facing up to the increase in the nonpartisan strata of voters in order to achieve the purpose above. To be precise, another purpose is to examine the theoretical synthesis of voting behavior from the viewpoint to analyze the attitudes and behaviors of nonpartisans instead of approaching from the stability or changing model of election.